ws-thredds/src/main/java/org/gcube/usecases/ws/thredds/NetUtils.java

58 lines
1.5 KiB
Java

package org.gcube.usecases.ws.thredds;
import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.net.HttpURLConnection;
import java.net.MalformedURLException;
import java.net.URL;
import org.apache.commons.io.IOUtils;
import lombok.extern.slf4j.Slf4j;
@Slf4j
public class NetUtils {
public static final File toFile(InputStream is) {
FileOutputStream outputStream =null;
try {
File toReturn=File.createTempFile("tempFile", ".tmp");
outputStream=new FileOutputStream(toReturn);
int read = 0;
byte[] bytes = new byte[1024];
while ((read = is.read(bytes)) != -1) {
outputStream.write(bytes, 0, read);
}
return toReturn;
}catch(Throwable t) {
throw new RuntimeException(t);
}finally {
if(outputStream!=null) {
IOUtils.closeQuietly(outputStream);
}
}
}
public static String resolveRedirects(String url) throws IOException{
log.debug("Resolving redirect for url {} ",url);
URL urlObj=new URL(url);
HttpURLConnection connection = (HttpURLConnection) urlObj.openConnection();
int status=connection.getResponseCode();
if(status>=300&&status<400){
String newUrl=connection.getHeaderField("Location");
log.debug("Following redirect from {} to {} ",url,newUrl);
return resolveRedirects(newUrl);
}else return url;
}
public static File download(String url) throws MalformedURLException, IOException {
return toFile(new URL(resolveRedirects(url)).openStream());
}
}